A synthesis apparatus for combining an image of scenery and an image of a person obtained by photography has already been realized. In an apparatus of this kind, the person is photographed in advance and the image of the person is extracted from the image obtained. The scenery is photographed separately from the person to obtain the scenery image. The extracted image of the person is combined with the image of the scenery (image data of the portion of the scenery image where the image of the person is to be placed is replaced by the image data representing the image of he person).
The photographic conditions that prevail when the image of the person is obtained (frontlighting or backlighting, indoor or outdoor, strobe photography or not, etc.) often differ from the photographic conditions which prevail when the image of scenery is obtained. If these photographic conditions differ, the composite image may appear unnatural.